Sawproof grating bar



- 'signaal-l noon AM al, mees@ .1. A. YOUNGBLQQD SAW-iROoF GRATING BAR Filed Aug. 9, '1947 TOR.

INVEN L @patented Apr, il, v I

narran .stares 2,503,537 v sawraoor enema aan l Samet a. "romances, nanas, i-reir. application auguste, i947, sarai No. 'zsm-azi a on.' (ci. 10a-eil' This invention relates to saw resisting grating bars and more particularly to bars adapted. to

cover prison or cell openings, bank or vault wiridows and the like which willdeieat efforts to saw through them."

The principal object oi the invention isto provide a protective barof the type set forth which consists of an elongated, cast metal body of any desired cross-sectional shape having one c or more cores, each comprised of a hollow and preferably cylindrical shape containing va, vplurality of spherical bodies ci hard substance such as agate. and having polished surfaces. Preferably two rows of these spherical bodies are provided in parallelism, 'the bodies being in st aggered relationship and .their degree of relativev displacement is predetermined to .preclude positional interchange from one rowto the other. Efforts to sever the bar as a whole as with a hack saw will bedefeated, due to the tendency of the tion of a saw.

individual spherical bodies to roll or revolvewith the motion oi the-saw. v

, Another object o2 the inventionis to provide a'v saw-proof bar which is permanently effective for the purpose described because of the vcorrosion and rust resisting characteristics of the material f of which the spherical bodies are made, thus preventing said spherical bodies from sticking by erosion in a 'xed position.

Another object of the invention is to provide' the spherical bodies in disconnected units so that *each of said units would turn 'individually with ease in its respective-`orbit vwhen contacted with saw or file, Still another object of the invention isi to provide means in the'tubularv cores of the bar to retain the spherical bodies in predeterminately spaced relationship.

With the foregoing objects in View, the inven-4 tion has further reference to certain features voi? accomplishment whichy will become apparent as the description proceeds, taken in connection with thev accompanying drawing wherein: l

Figure l is a fragmentary perspective view of a typical bar, partly in section." l

`Figure 2 is a fragmentary perspective View of a grating, showing bars constructed. according to the present invention.

Figure 3 is a longitudinal sectional View of a tubular core, b1 cken intermediate its ends to de- `Figure 4 is a fragmentary view of a core in longitudinal section, rotated 90 from the showing in liigure 3, and Figure is a fragmentary sectional. View. of a4 extends 'theiull length of the tube E bar showing the vball rack on which the balls are shown in dotted lines.

Protective grating or prison bars of various kinds and types have been heretofore devised with a view to defeating the action of a saw but these, for the most part are only partially efiecn tive since they consist oi parts ci continuous cica-- lgated units composed of materials vulnerable to the sticking and stifening eects oi'. rust and corrosion and since their eectiveness resides in their ability to 4yield in motion under the action of a saw, their fixation, due to rusting or corrosion, renders themA ineffective to defeat the ac- Continuing with a.- morev detailed description vof the drawing, reference numeral HJ denotes a .window or other opening protected by a grating consisting of bars it of identical' construction. Itis preferred that while the bars may be colli,

tively mounted in steel frames,` they be anchored. at shown, in the concrem or masonry opcznng of the window.

Each of the bars lIl consists of an' elongated, cast iron body of any desired shape in transverse,

section. The bar has one or more cores containing a metal tube i2, preferably of cylindrical shape. In fabricating the bars, the tubular cores are approximately arranged vertically in a mold form and molten metal is poured into thermold form around the cores which latter are co-axial with the resultant body'.

In each core tube il?. there is affixed', by spotlwelding at its ends, a racks: partition' i3 which On this rack or partitonrests two rows of relatively staggered spherical. bodies Mi. Thesespherical bodies are formed preferably from a hard rust resisting mineral such as agate or glass and their surfaces are' highly polished thus minimizing theyfriction oi the surfaces of said spherical bodies 'so as to permit each individual body or ball to revolve,v

should it be engaged by a saw for severing the body i! andtubular core i2.

'llie rack lil, for the purpose vof illustrating a sultai'le support for the balls or marbles li, and

fixing their relative position, isshown as consisting of a metal stamping defining a central rib, from the sides of which extend in staggered relationship a plurality of ngers I5, the ends of the latter resting on the walls of the core member I2 and to which certain of the fingers may be attached by any practical means, such as spotwelding, to hold the rack securely place, The position of theracl: in the tube Such. that the centers ci' the balls iii will Sie disposed ai: or

' escasez' t slightly above the longitudinal of the tube.

thus preventingV eny of the spherical bodies i@ vfrein being raised out of recess in rack.

The .timers i@ denne individuel recesses for tiieballe ifi iuwldch they easy naveiinitecl die placement but not sncl'i as to permit a saw siede te cnt diagonally through the bar and displace next ebli'acent thereto in the companion row.

The spherical bodiesor agate' marbles ifljoi each row are loosely arranged in therecesses-bef tween the fingers i8 ci the recit, as stated, yto permitoiindividual revolving movement thereby preventing their relative displacement. Hence it is impossible for the balls ci one row to exchangeplaces with or-become aligned with those of vthe companion row, thus insuring that at least one ball will offer an obstruction to a saw which has succeeded vin penetrating the body ii and core tube i2 and, in being free to rotate in any direc both the ball niet enaagedthereby and 'the "call displacement oi said spherical bodies but inenec# cess oi said rack and held thereby against other j than unlimited rotative movement.

3. A bar for protective gratings including a solid metallic body cast about a tubular core, a.

tion, the ball will defeat any further cutting of the saw. There is further the assurance that the "protection thus anorded will belong lasting and even after long periods of time it will serve equally as well for the purpose intended, clue te the nonl corrosive nature oi the balls Manifestly, the vcinistrnction as shown and' described is capable or some-modification and such mention as may be construed to fall within the scope andmeaning oi the appended claims is also considered to loc within the spirit and intent oi the invention. e

at is claimed is:

i.' A saw resisting-element including an elongated solid metal bar having longitudinally coeritensive and cylindrical pssssses, a 'plurality oi rows of hard spherical bodies in staggered rela- Y tionship in-eacn of'said passages and means coextensive with each of seid passages having staggered rows of parallel recesses receiving said spnericsi bodies sind ior restricting geometrical plurality of spherical bodlesof rust resisting substance in said cor-eend a rack dening a par-- tition coexterisive with said core anclhaving parallel rows oi staggered. recesses Ato retain. said spherical bodies. i

Li. A bar for protective gratings, comprising .a solid metallic body cast about a tubular core, a

' plurality of spherical bodies of rust resisting sub-' stance in said core and a rack dening a pertition substantially lessuin width than, the internal diameter of said core and having parallel rows ci staggered recesses receiving said spherical bodies to limit displacement of the spherical bodies collectively in the tubular core toa, distance less than the diameter of a single spherical body.

'JAMES A. YOUNGBLOOD.

nsrnnsnens einen The following-references are of record' in the file of this partent: 1

UNITED STATES PATENTS Number Name Bate 4110,947 Rogers Dec. i5, 1863 881,031; Schultz Mar. 3, 1908 1,4%93 Fiurgess `July 3l., 1923 2,156,579 Bayou .L r May 2, i939 

